Duke and Duchess of Cambridge join in remembering 100 year anniversary of the Battle of Passchendaele

Prime minister Theresa May (left) and The Duke and Duchess of Cambridge watch as the poppies fall from the roof of the Menin Gate in Ypres, Belgium for the official commemorations marking the 100th anniversary of the Battle of Passchendaele

The Duke and Duchess of Cambridge will join senior royals and politicians in commemorating the centenary of one of the bloodiest offensives of the First World War.

Prince William and Kate Middleton, Prince Charles, and Prime Minister Theresa May will be among those attending a ceremony marking 100 years since the Battle of Passchendaele.

More than 100 days of fighting in the summer and autumn of 1917, starting on July 31, left more than half a million men dead or injured on both sides.

Today's commemoration (July 31) centres on the Tyne Cot cemetery near Ypres in Belgium, the largest Commonwealth burial ground in the world with 11,971 servicemen buried or remembered there - with 8,373 of them identified.